Incineration is usually the method-of-choice to destroy diseased animal carcasses, especially in the case of Bovine Spongiform Encephalopathy or chronic wasting disease because of the presence of prions. These abnormally shaped proteins (called prions) are believed to be the cause of BSE and related diseases. However, research shows that the incineration process may not always destroy them.
An Indiana company, Waste Reduction by Waste Reduction, Inc., has patented a process using a solution of sodium or potassium hydroxide poured over a carcass inside a stainless steel container, then combined with heat to convert prions to harmless amino acids. When the process is complete, the entire animal mass is converted into a harmless slurry.
The science has been around for some time and is similar to that used by research laboratories to destroy contaminated lab animal carcasses.
The unit, which the company calls a digester, produces no toxic gasses and is cheaper to operate than an incinerator. USDA has purchased a unit, as has the Wisconsin Veterinary Diagnostic Laboratory — which is testing the digester on deer that have been afflicted with chronic wasting disease.
In the case of BSE surveillance, USDA officials say they expect to hold test animal carcasses in a cooler until conclusive BSE test results are available. Then, if any test positive for the disease, those carcasses will go through the digester rather than incineration. Animals that test negative will undergo the standard rendering process.